code: def labels():
      return [str(i) for i in range(10)]
  
imports: import matplotlib
  import matplotlib.pyplot
  import numpy
  import pandas
  import pytest
  from numpy.testing import assert_array_equal
  from nilearn.glm.first_level.design_matrix import make_first_level_design_matrix
  from nilearn.glm.tests._testing import design_with_null_durations
  from nilearn.plotting.matrix_plotting import pad_contrast_matrix, plot_contrast_matrix, plot_design_matrix, plot_event, plot_matrix
label_desc: Use image node_id 9 for calling a global function with example usage: labels() and returns: unknown